Silicone rubber ZY -850 suitable for the production of ordinary silicone products, such as silicone rubber buttons, sealing rings, etc. Appearance translucent solid, density 1.14±0.03, hardness 50±3, tensile strength 7.5, elongation 315, tear strength 11, shrinkage 3.2~3.6, rebound elasticty 60, plasticity 195±20, vulcanizing agent double 2.5.